Manufacture of briquettes



Juny 24, 192s; 1,463,094

T. RIGBY MANUFACTURE 0F BRIQUETTES Filed Nov. 2s. 1921 M Ill" Inl' NIH! r [im Ummm wlwmmlnlmw HW WW a? lill llmllmlm.

Patented July 24, 1923.

UNITED STATES THOMAS RIGBY, OF WESTMINSTER, LONDON, ENGLAND.

MANUFACTURE 0F BRIQUETTES.

Application filed November 23, 1921. Serial No. 517,300.l

To all whom t may concern.'

Be it known that I, THOMAS RIGBY, a subject of the King of England, residing at lVestminster, London, England, have invented certain new and useful Improvements in the Manufacture of Briquettes, of which the following is a specification.

The present invention is for improvements in and relating to the manufacture of briquettes.

The invention relates to the manufacture of briquettes in die presses of the type in which a plunger or ram accurately lits and is moved backward and forward in a working cavity or chamber, supplied at keach stroke of the ram with fresh material entering through a slot lor port which is alternately'opened and closed by the movement of the plunger or ram, the said plunger on its forward movement driving the material lto be briquetted` through taperingdies forming a reduced outlet from the Leind of the chamber, so that successive charges leave the chamber as a series of briquettes, which are discharged from the machine against the resistancel of an appropriate length of passage-way ofreduced size.

Such a briquette press is known as an open die briquetting press and the thickness of the briquettes made is dependent usually on the weight of material entering and filling the working chamber before the return or compression stroke of the plunger or ram. Consequently the thickness is also affected by the specific gravity of the material admitted to the working chamber.

The object of the present'invention is to provide a means for increasing the output of briquetted material from a briquetting` press of the type indicated.

According to this invention, a vprocess of briquetting is characterized by feeding the material to be briquetted, for example, peat, into the working chamber of the press under compression greater than that produced by the ordinary hopper-feed so that the material is submitted to the action of the ram in a precompressed condition. It is usual withsuch a press to obtain the initial resistance necessary for the manufacture of a hard briquette to build up such resistance gradually by means of admixture of oil with the peat dust. This has the effect of causing a partial resistance' and a briquette is made'havinga definite shape. The

proportion of oil in the mixture is gradually reduced and the briquettes produced becomev up the resistance necessitates usually a certain amount of manipulation by the attendant and the oil peat mixture isusually fed into the press by hand. Y. i Consequently provision is made in this` invention to enable this to be done either separately or in conjunction .with a device for precompressing the material. i

An apparatus'for carrying out the process .of this invention comprises the combination with a briquetting press, of the type indicated, of means, for example, a screw conveyor, for feeding the material to the working chamber of the press in a precompressed condition. v f

The apparatus in a specific form may comprise in combination with a briquetting press of the type described means for feeding material to the press from a source of supply independently of the compression device, or alternatively, through thev compression device such as a screw conveyor.-

The screw conveyor or the like may be driven by variable speed transmission-gear from the press driving mechanism. t

The accompanying. drawing is an elevation partly in section of onek form of briquettino press embodying this invention.

steam or other engine operates a main crank-shaft 1 having a crank-2 connected by a connecting rod 3 with a cross-.head 4, actuating a plunger or ram 5 operating in the working chamber of the press, the crank-shaft being preferably fitted witli"f1y wheels 7. f

The working chamber 6 communicates, by means of taper dies 8 at its further end, with a discharge passage 9 of the same dimensions as the smaller parts of the dies 8, and through which the briquettes are forced from-the .working chamber 6 .whichis'fed from a vertical feed-chamber `10. This vertical feed-chamber l0 is uncovered ,by the plunger 5 when vin the rearward'or outward position, and is completely covered when the plunger is at the forward or inward end of its stroke. As is customary in such presses the two vertical sides of the working chamberare fixed and' the upper wall 1l is vertically movable about apivot 12, the adjustthrough a hand-wheel 13, worm gearing 14 and a screw plunger 15. The raw material for the briquettes is supplied to the feedchamber 10 from a hopper y16, and inthe particular example 'described special arrangements are made for the type of feed which is used in the manufacture of briquettes from dried peat pulp; in that `process it is necessary to feed to the briquetting press in the first place "a quantity of oiled peat to set up the necessary frictional resistance between the die and 'the plunger. To allow of this the feed-hopper 16 is provided with a sliding door v17 by means of which the supply of material'can be cut off, and below the door 17 isla hand-hole 18 through which the oiled peat orsimilar starting material can be supplied. At the .bottomof the hopper is a smooth roller 19, which is driven in a counter clockwise direction; the material fed by the roller drops into the feed-chamber 10. /Vhen theA supply of starting aterial through the hand-holevlS is4 suificiu t, the

door' 17 may be opened soastoallow thev main supply to enter from the hopper 16. The amount of material fed by the smooth roller 19 can be regulated by a vertically adjusted'shutter 20. Between the bottom of the hopper 16 and the feed-chamber 10 (and to oneside of the smooth roller 19) l is arranged a screw conveyor 21 in a chamber n 22.1 The screwv conveyor chamber can be shut olf from the hopper when desired (for example, whenstarting up) by a sliding door23.

When'it is desired to feed the material from the hopper into the feed-chamber 10 under pressure, the sliding door 23 is moved away to allow of free passage from the hop! per Iinto the screw conveyor chamber. At the same time the shutter 2O may be lowered, or if desired, part of the feed may be allowed to pass directly over the smooth roller 19 into the feed-chamber 10, and part of the material may pass through the screw conveyor. y

A by-pass pipe 24 provided with a spring controlled valve 25 'connects the feed-chamber 10 with the hopper 16 so that if the pressure in the feed-chamber exceeds a certain I predetermined degree, the material in the feed screw or other mechanism employed` may be driven at such speed that the material is fed to the workingchamber at the ordinary normal pressure. As soon as briquetting proceeds satisfactorily the speed of the feed screws may be increased until the desired .degree of. compression is obtained.

In such a case the feed mechanism is advan tageously driven from the power supply of the press through variable speed kpower.

transmission gear, such' as cone pulleys or other similarly operable devices, by means ofl which the speed may be gradually increased until the desired conditions are obtained to meet the special case. n

F or forming briquettes of wet-carbonized peat the material fed to the hopper is in a powdered' or disintegrated condition, and

contains gases or air, which are more or less entangled in the material, and tend greatly to reduce its specific gravity, which in this condition may approximate to not more than .2, whereas the specific ygravity-of a finished briquette will be in the neighborhood of about 1.3.` Under these circumstances, it will be seen that the uncompressed material occupies about 6g; times the volume of the finished briquette, so that the thickness of briquette obtainable for a given stroke of the machine is small, and the output of briqueittes from the machine consequently limite f By opera-ting according to the present invention, the feeding of the peat to the press can readily beeffected at a pressure which is suflicient partly to compressv the peat and dispel therefrom a considerable quantity of the entrained gas. y v

The advantages of the invention (among which it is the aim of the invention -to include not only an increase in press output 'but also an overall economy of `power and the production of largery briquettes and of better briquettes, owing to the lesser amount of gas left to be expelled yfrom the powder at the briquetting stroke), willbe better appreciated when it is pointed out that it has been found practical to compress into'briquettes, of a specific gravity of aboutl 1.3, Yin a press of the type referred to, wet carbonized peat powder which, o-fsa gravity in the normal condition of 0.2, had been forced into the chamber of the press at a pressure giving the contents of the chamber before the advance of the plunger a gravity of a-bout 0.3, or again that similar results (that is to say a briquette gravity of about 1.3 and a powder gravity in the press chamber of about 0.3) can be obtained', With the comparatively flocculent product of the drying of raw peat pulp on a drum drier as a lilm Which is a powder of say a gravity of only 0.12 in the normal condition.

I claim:

l. In a briquetting apparatus, in combination, a Working chamber, a ram Working therein, a hopper 'or material to be briquetted, means for feeding` material in an uncompressed state from said hopper to the Working chamber, alternative means for forcing material from said hopper. into said Working' chamber, and means for rendering operative at Will either the feeding means or the forcing means.

2. In a briquetting apparatus, in combination, a Working chamber, a rain Working therein, a hopper for material to be briquetted, a drum beneath the hopper, means for rotating the drum at will to deliver ma 3. In a briquetting apparatus, in combiv nation, a Working chamber, a ram Working therein, a hopper for material to be briquetted, a drum beneath the hopper, means for rotating the drum at will to deliver material from the hopper to the Working chamber, a Worm-feed device adapted to deliver material from the hopper to the Working chamber independently of the drum, and in a pre-compressed state, a shutter adjustable at Will to control delivery of material from the hopper'to the drum, and a shutter. adjustable at Will to control delivery of mate rial from the hopper to the Worm-feed de- Vice.

In testimony whereof I aiiX my signature.

THOMAS RIGBY. 

